Cell type specific decoding of TGF-β2 production, signaling and outcome in the dynamics of cholestatic liver disease

In healthy and diseased livers, TGF-β2 is expressed in cholangiocytes and proliferating bile ducts with upregulation upon tissue damage and inflammation. How TGF-β2 and its downstream signaling pathways contribute to disease progression remains elusive. Here, we explored TGF-β2 expression dynamics, target cells and outcome with cell type specific resolution in patients with primary sclerosing cholangitis (PSC). Liver specimens from PSC patients were analysed by HE and IHC. Localization of TGF-β2 and TGFβR3 was determined via RNAscope. In silico analyses of 3 databases were performed to uncover upstream regulators of TGF-β2 expression including transcription factors. Cytokines, bile acids, and stressors were experimentally investigated in the human cholangiocyte cell line MMNK1 at mRNA and protein level using pharmacological inhibition of the respective signaling pathways. In PSC patients , TGF-β2 and TGFβR3 is predominantly located in non-parenchymal cells in periportal regions, indicating activated myofibroblasts and LSEC. Bioinformatic predictions of TGF-β2 promoter binding sites reveale d, among others, CREB1 as candidate for TGF-β2 induction. Bile acids including LCA, and combinations of UCDA, CDA, DCA induced TGF-β2 in cholangiocytes. Cell stressors as H₂O₂ upregulated TGF-β2 in MMNK1. FXR inhibition with GW4064 blunted TGF-β2 expression induced by LCA or H₂O₂. Spatial transcriptomics in PSC livers are performed to comparative profile TGF-β2 signaling activation. This study provides a cell type-resolved analysis of TGF-β2 and TGF-βR3 expression in tissue of PSC patients. New potential target sites of TGF-β2-driven disease progression were determined suggesting inhibition of TGF-β2 expression by inhibiting bile acid or H2O2 function may provide a therapeutic

Publication History

Article published online:
20 January 2025